Credit

Caption

Stomach mucosa. Light micrograph (bottom left) and computer illustration (top right) of the lining of the stomach, known as the mucosa. The stomach is a muscular sac involved in storage and digestion of food. The surface of the mucosa consists of simple columnar cells (dark purple in micrograph) that secrete mucus. The mucus protects the stomach lining from digestive acids and enzymes that act on food in the stomach. Beneath the columnar cells are gastric pits, the glands that make the acids and enzymes needed to digest food.